HLA class II polymorphisms associated with the physiologic characteristics defined by traditional Chinese medicine: Linking modern genetics with an ancient medicine

Objectives: The aim of this study was to test whether human leukocyte antigen (HLA) polymorphism contributes to the physical constitutions classified in Traditional Chinese Medicine (TCM). Design: Seven hundred six (706) individuals of the Han ethnic group inhabiting South China were classified into 7 TCM constitution groups, according to the criteria described in Theories of Physical Constitutions of Traditional Chinese Medicine, and the distributions of HLA-DRB1, DPB1, and DQB1 were investigated using the polymerase chain reaction-sequencing-based typing method. Results: The allele frequencies of DPB1*0501 in the Yin-deficiency group, DRB1*09012 in the Phlegm-wetness group, and DQB1*03032 in the Qi-deficiency and Phlegm-wetness groups were significantly different from that of the corresponding alleles in the Normality constitution, suggesting those alleles might be group-specific alleles and thus related to a particular constitution. Based on our analysis of serological groups of HLA, the associations of DR*04 with the Blood-stasis group and DQ*09 with the Qi-deficiency and Phlegm-wetness groups were observed. Conclusions: This was the first study to systematically investigate the relationship between HLA and TCM constitution using a high-resolution typing technique. The results suggested a genetic basis for the classification of physical constitution in TCM. This study laid the foundation, for the first time ever, toward gaining insight into the theory of traditional medicine using modern biological approaches.